Form Generator with React Hook Form & Zod

Generate production-ready React forms using React Hook Form, Zod validation schemas, and accessible shadcn/ui form controls. This skill creates forms with client-side and server-side validation, proper TypeScript types, and consistent error handling.

When to Use This Skill

Apply this skill when:

• Creating forms for entities (characters, locations, items, factions)
• Building data entry interfaces with validation requirements
• Generating forms with complex field types and conditional logic
• Setting up forms that need both client and server validation
• Creating accessible forms with proper ARIA attributes
• Building forms with multi-step or wizard patterns

Resources Available

Scripts

scripts/generate_form.py - Generates form component, Zod schema, and server action from field specifications.

Usage:

python scripts/generate_form.py --name CharacterForm --fields fields.json --output components/forms

scripts/generate_zod_schema.py - Converts field specifications to Zod schema with validation rules.

Usage:

python scripts/generate_zod_schema.py --fields fields.json --output lib/schemas

References

references/rhf-patterns.md - React Hook Form patterns, hooks, and best practices references/zod-validation.md - Zod schema patterns, refinements, and custom validators references/shadcn-form-controls.md - shadcn/ui form component usage and examples references/server-actions.md - Server action patterns for form submission

Assets

assets/form-template.tsx - Base form component template with RHF setup assets/field-templates/ - Individual field component templates (Input, Textarea, Select, Checkbox, etc.) assets/validation-schemas.ts - Common Zod validation patterns assets/form-utils.ts - Form utility functions (formatters, transformers, validators)

Form Generation Process

Step 1: Define Field Specifications

Create a field specification file describing form fields, types, validation rules, and UI properties.

Field specification format:

{
  "fields": [
    {
      "name": "characterName",
      "label": "Character Name",
      "type": "text",
      "required": true,
      "validation": {
        "minLength": 2,
        "maxLength": 100,
        "pattern": "^[a-zA-Z\\s'-]+$"
      },
      "placeholder": "Enter character name",
      "helpText": "The character's full name as it appears in your world"
    },
    {
      "name": "age",
      "label": "Age",
      "type": "number",
      "required": false,
      "validation": {
        "min": 0,
        "max": 10000
      }
    },
    {
      "name": "faction",
      "label": "Faction",
      "type": "select",
      "required": true,
      "options": "dynamic",
      "optionsSource": "api.getFactions()"
    },
    {
      "name": "biography",
      "label": "Biography",
      "type": "textarea",
      "required": false,
      "validation": {
        "maxLength": 5000
      },
      "rows": 8
    }
  ],
  "formOptions": {
    "submitLabel": "Create Character",
    "resetLabel": "Clear Form",
    "showReset": true,
    "successMessage": "Character created successfully",
    "errorMessage": "Failed to create character"
  }
}

Step 2: Generate Zod Schema

Use scripts/generate_zod_schema.py to create type-safe validation schema:

python scripts/generate_zod_schema.py --fields character-fields.json --output lib/schemas/character.ts

Generated schema includes:

• Field-level validation rules
• Custom refinements and transformations
• Type inference for TypeScript
• Error message customization
• Server-side validation support

Step 3: Generate Form Component

Use scripts/generate_form.py to create React Hook Form component:

python scripts/generate_form.py --name CharacterForm --fields character-fields.json --output components/forms

Generated component includes:

• React Hook Form setup with useForm hook
• Zod schema resolver integration
• shadcn/ui FormField components
• Proper TypeScript types inferred from schema
• Accessible form controls with ARIA labels
• Error display with FormMessage components
• Form submission handler with loading states
• Success/error toast notifications

Step 4: Create Server Action

Generate server action for form submission with server-side validation:

'use server'

import { z } from 'zod'
import { characterSchema } from '@/lib/schemas/character'
import { createCharacter } from '@/lib/db/characters'

export async function createCharacterAction(data: z.infer<typeof characterSchema>) {
  // Server-side validation
  const validated = characterSchema.safeParse(data)

  if (!validated.success) {
    return {
      success: false,
      errors: validated.error.flatten().fieldErrors
    }
  }

  // Database operation
  const character = await createCharacter(validated.data)

  return {
    success: true,
    data: character
  }
}

Step 5: Integrate Form into Page

Import and use generated form component in page or parent component:

import { CharacterForm } from '@/components/forms/CharacterForm'

export default function CreateCharacterPage() {
  return (
    <div className="container max-w-2xl py-8">
      <h1 className="text-3xl font-bold mb-6">Create New Character</h1>
      <CharacterForm />
    </div>
  )
}

Field Type Support

Supported field types and their shadcn/ui mappings:

• text → Input (type="text")
• email → Input (type="email")
• password → Input (type="password")
• number → Input (type="number")
• tel → Input (type="tel")
• url → Input (type="url")
• textarea → Textarea
• select → Select with SelectTrigger/SelectContent
• multiselect → MultiSelect custom component
• checkbox → Checkbox
• radio → RadioGroup with RadioGroupItem
• switch → Switch
• date → DatePicker (Popover + Calendar)
• datetime → DateTimePicker custom component
• file → Input (type="file")
• combobox → Combobox (Command + Popover)
• tags → TagInput custom component
• slider → Slider
• color → ColorPicker custom component

Validation Patterns

Common validation patterns using Zod:

String Validation

// Required with length constraints
z.string().min(2, "Too short").max(100, "Too long")

// Email
z.string().email("Invalid email")

// URL
z.string().url("Invalid URL")

// Pattern matching
z.string().regex(/^[a-zA-Z]+$/, "Letters only")

// Trimmed strings
z.string().trim().min(1)

// Custom transformation
z.string().transform(val => val.toLowerCase())

Number Validation

// Range validation
z.number().min(0).max(100)

// Integer only
z.number().int("Must be whole number")

// Positive numbers
z.number().positive("Must be positive")

// Custom refinement
z.number().refine(val => val % 5 === 0, "Must be multiple of 5")

Array Validation

// Array with min/max items
z.array(z.string()).min(1, "Select at least one").max(5, "Too many")

// Non-empty array
z.array(z.string()).nonempty("Required")

Object Validation

// Nested objects
z.object({
  address: z.object({
    street: z.string(),
    city: z.string(),
    zipCode: z.string().regex(/^\d{5}$/)
  })
})

Conditional Validation

// Refine with cross-field validation
z.object({
  password: z.string().min(8),
  confirmPassword: z.string()
}).refine(data => data.password === data.confirmPassword, {
  message: "Passwords must match",
  path: ["confirmPassword"]
})

Optional and Nullable Fields

// Optional (can be undefined)
z.string().optional()

// Nullable (can be null)
z.string().nullable()

// Optional with default
z.string().default("default value")

Form Patterns

Basic Form Structure

'use client'

import { useForm } from 'react-hook-form'
import { zodResolver } from '@hookform/resolvers/zod'
import { z } from 'zod'
import { Button } from '@/components/ui/button'
import {
  Form,
  FormControl,
  FormDescription,
  FormField,
  FormItem,
  FormLabel,
  FormMessage,
} from '@/components/ui/form'
import { Input } from '@/components/ui/input'
import { toast } from 'sonner'

const formSchema = z.object({
  name: z.string().min(2).max(100),
  email: z.string().email()
})

type FormValues = z.infer<typeof formSchema>

export function ExampleForm() {
  const form = useForm<FormValues>({
    resolver: zodResolver(formSchema),
    defaultValues: {
      name: '',
      email: ''
    }
  })

  async function onSubmit(values: FormValues) {
    try {
      const result = await submitAction(values)
      if (result.success) {
        toast.success('Submitted successfully')
        form.reset()
      } else {
        toast.error(result.message)
      }
    } catch (error) {
      toast.error('An error occurred')
    }
  }

  return (
    <Form {...form}>
      <form onSubmit={form.handleSubmit(onSubmit)} className="space-y-6">
        <FormField
          control={form.control}
          name="name"
          render={({ field }) => (
            <FormItem>
              <FormLabel>Name</FormLabel>
              <FormControl>
                <Input placeholder="Enter name" {...field} />
              </FormControl>
              <FormDescription>Your display name</FormDescription>
              <FormMessage />
            </FormItem>
          )}
        />

        <FormField
          control={form.control}
          name="email"
          render={({ field }) => (
            <FormItem>
              <FormLabel>Email</FormLabel>
              <FormControl>
                <Input type="email" placeholder="you@example.com" {...field} />
              </FormControl>
              <FormMessage />
            </FormItem>
          )}
        />

        <Button type="submit" disabled={form.formState.isSubmitting}>
          {form.formState.isSubmitting ? 'Submitting...' : 'Submit'}
        </Button>
      </form>
    </Form>
  )
}

Array Fields with useFieldArray

import { useFieldArray } from 'react-hook-form'
import { Button } from '@/components/ui/button'

// In schema
const formSchema = z.object({
  tags: z.array(z.object({
    value: z.string().min(1)
  })).min(1)
})

// In component
const { fields, append, remove } = useFieldArray({
  control: form.control,
  name: 'tags'
})

// In JSX
{fields.map((field, index) => (
  <div key={field.id} className="flex gap-2">
    <FormField
      control={form.control}
      name={`tags.${index}.value`}
      render={({ field }) => (
        <FormItem className="flex-1">
          <FormControl>
            <Input {...field} />
          </FormControl>
          <FormMessage />
        </FormItem>
      )}
    />
    <Button type="button" variant="destructive" size="icon" onClick={() => remove(index)}>
      X
    </Button>
  </div>
))}
<Button type="button" onClick={() => append({ value: '' })}>
  Add Tag
</Button>

File Upload with Preview

const [preview, setPreview] = useState<string | null>(null)

<FormField
  control={form.control}
  name="avatar"
  render={({ field: { value, onChange, ...field } }) => (
    <FormItem>
      <FormLabel>Avatar</FormLabel>
      <FormControl>
        <Input
          type="file"
          accept="image/*"
          {...field}
          onChange={(e) => {
            const file = e.target.files?.[0]
            if (file) {
              onChange(file)
              const reader = new FileReader()
              reader.onloadend = () => setPreview(reader.result as string)
              reader.readAsDataURL(file)
            }
          }}
        />
      </FormControl>
      {preview && (
        <img src={preview} alt="Preview" className="mt-2 h-32 w-32 object-cover rounded" />
      )}
      <FormMessage />
    </FormItem>
  )}
/>

Conditional Fields

const showAdvanced = form.watch('showAdvanced')

<FormField
  control={form.control}
  name="showAdvanced"
  render={({ field }) => (
    <FormItem className="flex items-center gap-2">
      <FormControl>
        <Switch checked={field.value} onCheckedChange={field.onChange} />
      </FormControl>
      <FormLabel>Show Advanced Options</FormLabel>
    </FormItem>
  )}
/>

{showAdvanced && (
  <FormField
    control={form.control}
    name="advancedOption"
    render={({ field }) => (
      <FormItem>
        <FormLabel>Advanced Option</FormLabel>
        <FormControl>
          <Input {...field} />
        </FormControl>
        <FormMessage />
      </FormItem>
    )}
  />
)}

Accessibility Considerations

Ensure forms are accessible by:

1. Proper Labels: Every form control must have an associated FormLabel
2. Error Messages: Use FormMessage to announce validation errors
3. Descriptions: Use FormDescription for helpful context
4. Required Fields: Mark required fields visually and in ARIA attributes
5. Focus Management: Ensure logical tab order and focus indicators
6. Keyboard Navigation: All controls operable via keyboard
7. ARIA Attributes: FormField automatically sets aria-describedby and aria-invalid
8. Error Summary: Consider adding error summary at top of form for screen readers

Testing Generated Forms

Test forms using React Testing Library and Vitest:

import { render, screen, waitFor } from '@testing-library/react'
import userEvent from '@testing-library/user-event'
import { CharacterForm } from './CharacterForm'

describe('CharacterForm', () => {
  it('validates required fields', async () => {
    render(<CharacterForm />)

    const submitButton = screen.getByRole('button', { name: /submit/i })
    await userEvent.click(submitButton)

    expect(await screen.findByText(/name is required/i)).toBeInTheDocument()
  })

  it('submits valid data', async () => {
    const mockSubmit = vi.fn()
    render(<CharacterForm onSubmit={mockSubmit} />)

    await userEvent.type(screen.getByLabelText(/name/i), 'Aragorn')
    await userEvent.click(screen.getByRole('button', { name: /submit/i }))

    await waitFor(() => {
      expect(mockSubmit).toHaveBeenCalledWith({
        name: 'Aragorn'
      })
    })
  })
})

Common Use Cases for Worldbuilding

Character Creation Form

Fields: name, race, faction, class, age, appearance, biography, relationships, attributes, inventory

Location Form

Fields: name, type, region, coordinates, climate, population, government, description, points of interest

Item/Artifact Form

Fields: name, type, rarity, owner, location, properties, history, magical effects, value

Event/Timeline Form

Fields: title, date, location, participants, description, consequences, related events

Faction/Organization Form

Fields: name, type, leader, headquarters, goals, allies, enemies, members, history

Implementation Checklist

When generating forms, ensure:

• Zod schema created with all validation rules
• Form component uses zodResolver
• All field types mapped to appropriate shadcn/ui components
• FormField used for each field with proper render prop
• FormLabel, FormControl, FormMessage included for each field
• Form submission handler with error handling
• Loading states during submission
• Success/error feedback (toasts or messages)
• Server action created with server-side validation
• TypeScript types inferred from Zod schema
• Accessibility attributes present
• Form reset after successful submission
• Proper default values set

Dependencies Required

Ensure these packages are installed:

npm install react-hook-form @hookform/resolvers zod
npm install sonner  # for toast notifications

shadcn/ui components needed:

npx shadcn-ui@latest add form button input textarea select checkbox radio-group switch slider

Best Practices

1. Co-locate validation: Keep Zod schemas close to form components
2. Reuse schemas: Share schemas between client and server validation
3. Type inference: Use z.infer<typeof schema> for TypeScript types
4. Granular validation: Validate on blur for better UX
5. Optimistic updates: Show success state before server confirmation when appropriate
6. Error recovery: Allow users to easily fix validation errors
7. Progress indication: Show loading states during async operations
8. Data persistence: Consider auto-saving drafts for long forms
9. Field dependencies: Use form.watch() for conditional fields
10. Performance: Use mode: 'onBlur' or 'onChange' based on form complexity

Troubleshooting

Issue: Form not submitting

• Check handleSubmit is wrapping onSubmit
• Verify zodResolver is configured
• Check for validation errors in form state

Issue: Validation not working

• Ensure schema matches field names exactly
• Check resolver is zodResolver(schema)
• Verify field is registered with FormField

Issue: TypeScript errors

• Use z.infer for type inference
• Ensure form values type matches schema type
• Check FormField generic type matches field value type

Issue: Field not updating

• Verify field spread {...field} is applied
• Check value/onChange are not overridden incorrectly
• Use field.value and field.onChange for controlled components

Additional Resources

Consult references/ directory for detailed patterns:

• references/rhf-patterns.md - Advanced React Hook Form patterns
• references/zod-validation.md - Complex validation scenarios
• references/shadcn-form-controls.md - All form component variants
• references/server-actions.md - Server-side form handling

Use assets/ directory for starting templates:

• assets/form-template.tsx - Copy and customize
• assets/field-templates/ - Individual field implementations
• assets/validation-schemas.ts - Common validation patterns